Abstract: A motor includes a magnet formed into a hollow disc shape and having at least one flat surface circumferentially divided and alternately magnetized to opposite poles, a first coil having an inner peripheral surface opposing the outer peripheral surface of the magnet, a second coil having an outer peripheral surface opposing the inner peripheral surface of the magnet, first magnetic pole portions opposing one flat surface of the magnet, formed from a plurality of teeth extending in the radial direction of the magnet, and excited by the first coil, second magnetic pole portions formed on the opposite side to the first magnetic pole portions via the magnet at positions opposing the first magnetic pole portions, third magnetic pole portions opposing one flat surface of the magnet, formed from a plurality of teeth extending in the radial direction of the magnet, and excited by the second coil, and fourth magnetic pole portions formed on the opposite side to the third magnetic pole portions via the magnet at positi

Abstract: A very thin fan motor with an attached heat sink that has high heat radiation and air cooling effects in a small, flat, thin package, that has a simple and easily assembled overall structure as a fan motor, and that has superior cooling efficiency.

Abstract: A motor providing unidirectional rotational motive power is provided. The motor has a generally circular stator with a stator axis, an outer surface, and a circumferential line of demarcation at about a midpoint of the outer surface. The motor also includes one or more stator magnets attached to the outer surface of the stator. The stator magnets are arranged in a generally circular arrangement about the stator axis and generate a first magnetic field. An armature is attached to the stator for rotation therewith, the armature having an axis parallel to the stator axis. One or more rotors, are spaced from the armature and coupled thereto by an axle for rotation about an axis of each rotor, each rotor rotating in a plane generally aligned with the armature axis. Each rotor includes one or more rotor magnets, with each rotor magnet generating a second magnetic field.

Abstract: A motor having a short axial length and a large torque, including a disk-shaped rotor having at least one plane magnetized in a plurality of different poles in a rotational direction thereof, a coil arranged such that an inner circumferential surface of the coil faces an outer circumferential surface of the rotor, or an outer circumferential surface of the coil faces an inner circumferential surface of the rotor, a first magnetic pole portion that faces a plane of the rotor, is formed with teeth extending in a radial direction of the rotor, and can be excited by the coil, and a second magnetic pole portion that is provided on a side of the rotor opposite the first magnetic pole portion such that the first and second magnetic pole portions sandwich the rotor, and can be excited by the coil.

Abstract: The radial/rotary propulsion system of the present invention features a flywheel having concentric rings of permanent magnets attached to one or both sides. These permanent magnets interact with DC powered electromagnets which, when selectively energized, impart rotary motion to the flywheel. By arranging the permanent magnets in concentric rings, better control of both speed and torques may be obtained. In addition, in a regenerative mode, inertia of the flywheel is reconverted to electrical energy by either additional permanent magnet/coil combinations or through the switching of the electromagnet coils normally used for rotating the flywheel. In alternated embodiments, regeneration is accomplished with alternators interacting with other magnets of the flywheel. The regenerative mode is also helpful in braking the flywheel as its inertial energy is converted to electrical energy.

Abstract: A toroidal AC generator includes an outer casing and an annular stator core of ferromagnetic material which is encased in a hollow annular cover of plastics material and which is fixed to the casing between the discs of a twin disc rotor. Each rotor disc carries a circular array of alternately polarised permanent magnets which face the stator core. The hollow annular cover is a two-part moulding and is formed of radially inner and outer ring portions which are joined by circular arrays of radial ribs which extend across the opposed radial faces of the annular core and form open-ended radial passages for the electrical phase windings which are wound around the cover. The ribs project radially beyond the radially outer ring portion and form hooks around which a winding may be retained temporarily during winding.

Abstract: An alternating current electrical generator creates three different and distinct magnetic fields between would coil elements and rotating magnets, two fields of which are induced fields caused by magnet rotation. A plurality of magnets are positioned such that they extend outwardly from a rotating shaft. The magnets are circumferentially spaced around the shaft such that the north polar end of one magnet follows the south polar end of the next magnet or such that the polar end of one magnet follows a magnet with the same polar end. A plurality of stationary coil elements are positioned in spaced relation to the magnets. The coil elements each have electrical windings and metal cores which extend the lengths of the coil elements. The magnets rotate in spaced relation to the ends of the coil elements in such a way that the magnets' flux lines cut the cores located at the center of each of the coil elements. This induces alternating electric current that oscillates back and forth along the lengths of the cores.

Abstract: For the purpose of preventing resin from flowing into a commutator when resin molding a rotor, a rotor for a flat coreless motor comprises a printed wiring board, on one side of which a plurality of air-cored armature coils are provided, and on the other side of which a plurality of segment patterns constituting a commutator and a wiring pattern are provided. These members are molded with resin into a unitary body with the segment patterns exposed. Wiring pattern parts are provided so as to surround the outer periphery of the commutator.

Abstract: A unitary amorphous metal magnetic component for an axial flux electric machine such as a motor or generator is formed from a spirally wound annular cylinder of ferromagnetic amorphous metal strips. The cylinder is adhesively bonded and provided with a plurality of slots formed in one of the annular faces of the cylinder and extending from the inner diameter to the outer diameter of the cylinder. The component is preferably employed in constructing a high efficiency, axial flux electric motor. When operated at an excitation frequency “f” to a peak induction level Bmax the unitary amorphous metal magnetic component has a core-loss less than “L” wherein L is given by the formula L=0.0074 f (Bmax)1.3+0.000282 f1.5 (Bmax)2.4, the core loss, excitation frequency and peak induction level being measured in watts per kilogram, hertz, and teslas, respectively.

Abstract: An electrical machine comprises a magnetically permeable ring-shaped core centered on an axis of rotation and having two axially-opposite sides. Coils are wound toroidally about the core and disposed sequentially along the circumferential direction. Each coil includes two side legs extending radially alongside respectively sides of the core. Coil-free spaces exist between adjacent side legs. A bracket has first and second side flanges that are connected by a bridging structure and respectively abut the first and second sides of the coil.

Abstract: The present invention relates generally to a magnet motor, and having being provided the driven power of the electromagnet motor for electric vehicles, wherein, it has provided with a wireless coil whole rotator, which the upper part has been constructed with an equal angle, a power perpetual magnet is provided. At least one set of a magnet pole coil is formed into an electromagnet pole module and a circuit control unit. Using the perpetual magnet and the less electricity consumption of an electric magnet pole generates the repelling torque, accomplishing the object of the turning rotator to generate power. Either it is coupled with a simple or a complex structure; it can apply to be the driven motor of a bicycle, a motorcycle and a car. Moreover, it can greatly reduce the consumption of the vehicle battery electricity, and make it to be an environmental protection and practical vehicle means.

Abstract: An electromagnetic circuit that may be advantageously employed in an articulated camera, such as a CCTV camera, as a part of a servo mechanism to directly drive the camera and optical lens assembly, for example, in the pan and/or tilt axes. In one embodiment, the coil assembly of the servo mechanism may comprise four separate coils that rotate about the center of the ring shape of a single one-piece ring-shaped permanent magnet that has been pre-magnetized in two pair of opposing polarities. The magnet assembly that includes the magnet ring, may be bonded to a circular plate made of ferrous metal.

Abstract: A flat rotary electric generator includes at least one toroidal coil structure for cutting magnetic lines to induce a current and at least one disc-shaped magnetic pole structure oriented parallel to the helical coil structure. If multiple toroidal coil structures and disc-shaped magnetic coil structures are included, the toroidal coil structures and disc-shaped magnetic coil structures are arranged in alternating manner. The toroidal coil structure and disc-shaped magnetic pole structure are not provided with a permeable material. When either the toroidal coil structures or the at least one disc-shaped magnetic pole structure is rotated by an external force, the toroidal coil structure cuts the magnetic lines passing therethrough to generate an induced current.

Abstract: A single magnetic conductive plate for a single pole plate brushless dc motor comprises a pole plate, a plurality of pole faces, and an axial hole. The pole plate, the pole faces and an axial hole are integrated into the single magnetic conductive plate. The pole plate is regarded as a base and adapted to combine with a coil to form a stator. The pole faces are punched and equi-spaced round the axial hole proximal the coil. The axial hole is adapted to combine with a mounting seat for supporting a rotor.

Abstract: Dynamo electric machines and stators for use in such machines are provided. The stators comprise plates configured to be substantially flat and a plurality of spaced apart projections or teeth extending away from the plate and, together with the plate defining a plurality of slots therebetween. The stators comprise masses of metal particles. Using stators made from such metal particles provides enhanced machine efficiency, which is believed to be because of reduced eddy current effects in the stator. Motors including rotors having generally flat arrays of permanent magnetic poles and such stators which are spaced apart from and generally facing the permanent magnetic poles and have a plurality of magnetic windings, and pumps powered by such motors are included within the scope of the present invention.

Abstract: A flat rotary electric generator includes at least one toroidal coil structure for cutting magnetic lines to induce a current and at least one disc-shaped magnetic pole structure oriented parallel to the helical coil structure. If multiple toroidal coil structures and disc-shaped magnetic coil structures are included, the toroidal coil structures and disc-shaped magnetic coil structures are arranged in alternating manner. The toroidal coil structure and disc-shaped magnetic pole structure are not provided with a permeable material. When either the toroidal coil structures or the at least one disc-shaped magnetic pole structure is rotated by an external force, the toroidal coil structure cuts the magnetic lines passing therethrough to generate an induced current.

Abstract: A rotary electric machine comprises a rotating shaft 7 rotatably supported by bearings 2, 3, a rotor 23 attached integrally with the rotating shaft 7, and a stator 5 arranged facing the rotor 23. The stator 5 includes a plurality of coils arranged substantially in a circular (annular) form in a rotating direction of the rotating shaft 7. The rotor 23 includes a circular-disc rotor yoke 26 made of a ferromagnetic material, such as iron. Depressed portions and raised portions 28 on a surface of the rotor yoke 26 facing the stator 5, except for the center portion, are arranged in a circumferential direction of the rotor yoke 26. N-pole magnets 29 and S-pole magnets 30 are alternately arranged in the depressed portions 27. Therefore, in addition to torque generated by the magnets 29, 30, reluctance torque is generated between the raised portions 28 on the rotor yoke side 26 and the teeth on the stator side 25, thus making it possible to increase the range of rotation speeds of the motor.

Abstract: A rotor disc assembly (10) for an AC machine includes a rotor disc (20), permanent magnets (30) and a spider (40). The rotor disc (10) has a circumferential lip (22) projecting from a surface thereof. The permanent magnets (30) are positioned in a circular array on the surface of the rotor disc (20), with constant angular pitch, and so as to lie against the lip (22). The spider includes an annular base portion (41), with a plurality of arms (42) projecting radially outwards therefrom. The spider (40) is fixed to the surface of the rotor disc (20) such that each arm (42) is between and abuts a respective juxtaposed pair of the permanent magnets (30). The arms (42) and the members (30) are each provided with cooperating wedge-shaped cross sections such that each arm (42) constrains the respective two permanent magnets (30) both axially and tangentially on the surface of the rotor disc (20).

Abstract: An electric rotating machine including a casing, two disk-shaped rotors arranged in concentric relation to each other within the casing, and a stator disposed concentrically with the rotors within the casing. The rotors include magnets, respectively. The magnet of one of the rotors and the magnet of the other of the rotors are disposed radially offset from each other. The stator includes a radially outer portion axially opposed to the magnet of one of the rotors and a radially inner portion axially opposed to the magnet of the other of the rotors.

Abstract: The present invention relates generally to a magnet motor, and having being provided the driven power of the electromagnet motor for electric vehicles, wherein, it has provided with a wireless coil whole rotator, which the upper part has been constructed with an equal angle, a power perpetual magnet is provided. At least one set of a magnet pole coil is formed into an electromagnet pole module and a circuit control unit. Using the perpetual magnet and the less electricity consumption of an electric magnet pole generates the repelling torque, accomplishing the object of the turning rotator to generate power. Either it is coupled with a simple or a complex structure; it can apply to be the driven motor of a bicycle, a motorcycle and a car. Moreover, it can greatly reduce the consumption of the vehicle battery electricity, and make it to be an environmental protection and practical vehicle means.

Abstract: An energy conversion magnetic circuit is constituted with magnet pole pieces of magnets or armatures which are in parallel with respect to the shaft to obtain a dynamic force or an electromotive force. The magnetic circuit for a generator or an electric motor has a rotating shaft, a plurality of supporters fixedly mounted in a perpendicular direction to the circumference of the rotating shaft, a plurality of rotors arranged in parallel with respect to the shaft on each end of the plurality of supporters to be rotated by attraction force and repulsion force of a magnetic field, and a plurality of armatures having a coil wound on the body thereof. The coil is mounted at an interval outside the rotors and receives induced alternate magnetic flux of the rotors to generate a rectangular wave electromotive force or to obtain a high torque with input of electrical energy.

Abstract: The integrated planer motor assembly consists of two parts: a. A integrated planer stator assembly that combines the motors stator coils, biased MR sensors and the motor's variable speed control IC into a single part using advanced high volume semi-conductor manufacturing processes; b. A planer rotor assembly having a precise planer surface containing the high energy permanent magnet and the ceramic ferrite return structure. The rotor assembly is assembled to the stator assembly using a precision washer to establish the motors small and precise air gap thus maximizing magnetic flux density.

Abstract: A revolution type actuator having a movable member performing a revolution motion includes a movable member capable of revolving with respect to a fixed member, a plurality of conducting paths which are provided on a face parallel to a trajectory face of the above-mentioned revolution motion and through which currents flow in mutually intersecting directions, power supply which flows currents having different phases through the above-mentioned plurality of conducting paths, and a magnetic field generator which forms a magnetic field perpendicular to the above-mentioned conducting path, in which the above-mentioned movable member revolves due to an electromagnetic force generated by an interaction between a current flowing through said conducting path and a magnetic field generated by the above-mentioned magnetic field generator.

Abstract: A motor for incorporation in an actuator pivot includes a coil disk, an upper magnet-yoke disk, and a lower magnet-yoke disk. The coil disk is attached to the pivot shaft to form a shaft-coil assembly. The coil disk includes a plurality of coils, each placed orthogonally to the axis of the shaft. Each coil is configured to receive an electrical current in a first direction. A second coil located diametrically opposite to the first coil is configured to receive a second electrical current in a second direction so that the coils generate a torque with a net resultant linear force being substantially equal to zero. The first magnet-yoke disk, for mounting relative to the shaft at a location above the coil disk so that the first magnet-yoke disk rotates with respect to the coil disk, the magnet-yoke ring comprising at least one magnet, aligned in a first direction, and a respective plurality of yokes, each yoke for holding at least one magnet such that magnetic lines of flux are generated parallel to the axis.

Abstract: A unitary amorphous metal magnetic component for an axial flux electric machine such as a motor or generator is formed from a spirally wound annular cylinder of ferromagnetic amorphous metal strips. The cylinder is adhesively bonded and provided with a plurality of slots formed in one of the annular faces of the cylinder and extending from the inner diameter to the outer diameter of the cylinder. The component is preferably employed in constructing a high efficiency, axial flux electric motor. When operated at an excitation frequency “f” to a peak induction level Bmax the unitary amorphous metal magnetic component has a core-loss less than “L” wherein L is given by the formula L=0.0074 f (Bmax)1.3+0.000282 f1.5 (Bmax)2.4, the core loss, excitation frequency and peak induction level being measured in watts per kilogram, hertz, and teslas, respectively.

Abstract: An electric motor with rotor being a drive wheel. The drive wheel has one or more permanent magnets attached to said drive wheel with opposite magnetic poles adjacent to one another. One or more electromagnets are attached to the structure to which the drive wheel is rotatably connected. A sensor determines the location of the permanent magnets. This information is utilized to assure that the electromagnets are energized only when the resultant magnetic fields will interact with the magnetic fields of the permanent magnet to produce a force on the drive wheel that will cause rotation in the desired direction. Three principal embodiments are employed. In a first embodiment, a computer periodically activates a switch to send pulsed voltage to the electromagnets; the percentage of the period of each pulse during which the voltage is non-zero determines the speed of the drive wheel. In a second embodiment, the computer is replaced with a timing circuit that controls the switch.

Abstract: Disclosed is a permanent magnet generator incorporated in a 3.5″ diskette that can be used as an input/output adapter for memory cards that can generate a power generation output of 40 mW or more when the rotor of the generator is rotated at 300 rpm. The permanent magnet generator has such a construction that rotor magnetic poles are provided only on one end face of a disc-shaped permanent magnet serving as a rotor, a plurality of stator magnetic poles are provided only on that end face of the permanent magnet in such a manner as to face the rotor magnetic poles, and a soft magnetic hub is fixedly fitted to the other end face of the permanent magnet. Even when a bonded NdFeB magnet is used as the permanent magnet, a sufficient power can be produced.

Abstract: An axial gap motor-generator of the type coupled to a shaft having an axis of rotation. The motor-generator comprises a rotor having a rotor body rotatably disposed about the shaft and having an outer region. The rotor includes a plurality of openings disposed in the outer region and spaced from one another. Each of the openings includes an outer edge. The motor-generator also includes a plurality of magnets equal in number to the openings. Each of the magnets includes an outer edge corresponding to the outer edge of a corresponding one of the openings. The outer edge of the magnets generally is non-conformal to and is slightly smaller than the outer edge of the openings, and each of the magnets is shaped to be inserted into the corresponding one of the openings. The motor-generator further includes a stator assembly positioned adjacent to the rotor. The stator assembly includes windings positioned to be adjacent to the magnets when the rotor is rotated.

Abstract: A rotor (10) for a miniature electric motor includes a magnet (12) having a rotation axis (14) and a shaft (16) fixed concentrically to the magnet. The magnet (12) includes a through hole (20) extending coaxially with the rotation axis (14). The shaft (16) includes a portion (24) fitted in the through hole (20). The portion (24) has an axial interengagement length (t1) shorter than an axial length (T1) of the through hole (20). The rotor (10) also includes reinforcing means provided at least inside the through hole (20). The magnet (12) comprises an annular magnet material (18), and a coating (22) formed on a surface of the magnet material and arranged at least inside the through hole (20). The reinforcing means is formed as the coating (22) of the magnet (12), and acts to ensure a fixing force to securely hold the shaft (16) in a predetermined position on the magnet.

Abstract: A generator build in a wheel nave, is disclosed. The wheel nave and a casing (2), enclosing the generator rotate around a fixed wheel axis (1). The generator comprises a coil (14) concentric with the wheel axis and fixed to wheel axis (1). The generator is especially characterized in that magnets are provided, concentric with the coil (14) turning a first group with alternating N- and S-magnet poles (21, 22) to a first plane, and a second group with alternating N- and S-magnet poles to an opposite second plane. A first and a second pole changer (12, 13) are provided to rotate in relationship to the wheel axis (1), whereas during the rotation one of the pole changers (12) passes relatively close to the first group of magnet poles and the second pole changer (13) passes relatively close to the second group of magnet poles.

Abstract: An electrical machine comprises a magnetically permeable core. The core is elongated to thereby define a lengthwise direction and a profile that is transverse to the lengthwise direction. Coils are wound about the core profile and sequentially disposed along the lengthwise direction. The core profile has a surface that is bowed outward.

Abstract: A brushless motor includes a rotor position detecting device disposed between stator teeth, rather than directly below a rotor magnet, so that the distance between a lower end of a rotor magnet and a stationary frame is minimized. This results in a thinner brushless motor than conventional designs. In the preferred embodiment of the present invention, the rotor position detecting device is a Hall device.

Abstract: Disclosed is a multi-phase flat-type PM stepping motor comprising a first motor unit having a first stator unit and a first rotor unit, and a second motor unit having a second stator unit and a second rotor unit. The first stator unit has a plurality of air-core coils that are radially arranged on a first isolating magnetic disc. The first rotor unit has a plurality of permanent magnets that are alternatively magnetized in N-pole and S-pole and radially arranged on a second magnetic disc with a predetermined air gap with respect to the coil surface of the first stator unit. In the same manner, the second stator unit has a plurality of air-core coils that are radially arranged on a third isolating magnetic disc, and the second rotor unit has a plurality of permanent magnets arranged on a fourth magnetic disc. The first and second motor units are coaxial and symmetric with each other about a non-magnetic disc arranged therebetween.

Abstract: The present invention aims at providing a motor having short axial length and large torque. For an object concerned, a motor according to the present invention has the structure of comprising an approximately disk-shaped rotor that is dividedly magnetized so that at least one plane may become a plurality of polarities in a rotational direction, a coil that has an inner circumferential surface facing an outer circumferential surface of the rotor, or an outer circumferential surface facing an inner circumferential surface of the rotor, a first magnetic pole portion that extends in a radial direction of the rotor and is magnetized by the coil while facing a surface of the rotor, and a second magnetic pole portion that is magnetized by the rotor.

Abstract: An axial pole motor includes a stator (9) and a rotor (3) which face one another across a plane perpendicular to the rotor axis, the stator having coil windings (12) substantially uniformly circumferentially spaced and lying in planes substantially perpendicular to the rotor axis defining a number of stator poles (11), the rotor also including a number of rotor poles (4) comprising one or more permanent magnets. The number of stator poles (11) is different from the number of rotor poles (4) and the stator poles (11) and rotor poles (4) are of substantially the same size and shape to provide a pole overlap pattern in which when any one rotor pole completely covers a facing stator pole, the difference between the number of rotor poles and the number of stator poles which exist between that rotor pole and the next rotor pole which completely covers a facing stator pole is one.

Abstract: A stepping motor comprises a stator (3) with at least two magnetic circuits and a rotor (2) that is rotatably mounted on the stator through a single ball bearing having four contact points. The rotor comprises a mutipolar magnet (5) essentially in the form of a disc having a central opening (6). One rotor portion (7) is fixed at one radially external portion of the magnet (5), while one radially internal portion of the magnet is arranged within the air gap of said magnetic circuits.

Abstract: A D.C. brushless voice-coil motor is a miniature motor with a very small dimension. It has conduction coils to serve as the stator of the motor and a magnetic element which has a plurality of magnetic poles located at the same plane to serve as the rotor to simplify the components needed in the motor for achieving the miniaturization requirements. The motor includes at least a circuit board, at least two conduction coils and a magnetic element. The induction coils are located on the circuit board for generating magnetic force when receiving electric power and function as the stator of the motor. The magnetic element is located above the induction coils and has a plurality of co-plane magnetic poles to function as the rotor of the motor. Input electric power will generate inductive magnetic field, and under the interaction between the induction coils and magnetic element, the magnetic element will generate rotational kinetic energy.

Abstract: An interior permanent magnet synchronous motor capable of significantly restraining cogging torque and torque pulsation during feeding of electricity thereto. Each of the outer peripheral surface sections of a rotor core and a magnetic pole surface of each of magnetic poles of a stator core are arranged so as to have a gap defined therebetween and having a size &dgr;d which satisfies an expression &dgr;d=&dgr;d0/cos(p&thgr;d), wherein &dgr;d0 is a size of the gap which is determined along a virtual center line defined so as to extend through centers of two virtual lines extending from a center of a shaft through both ends of the outer peripheral surface section defined in a peripheral direction thereof and &thgr;d is an angle between the virtual central line and each of the virtual lines.

Abstract: A rotor assembly of a brushless direct current motor includes a body provided with a circuit board, a pole plate, a coil, and a shaft base. The shaft base is provided with a positioning hole having a threaded portion by which a fixing member can be combined with a rotor. The rotor is provided with a countersunk seat in which a bearing is placed. The bearing has an axial hole for allowing passage of the fixing member so as to fix it. The rotor takes the fixing member as a center so as to rotate by a permanent magnet inducing with the coil.

Abstract: A single-stator-double-rotor rotating motor has one upper-layer rotor, one intermediate-layer armature and one lower-layer rotor. The upper-layer rotor and lower-layer rotor are embedded with the same number of magnets to form a magneto type magnetic pole, stator electrodes of the same number as the number of magnets are disposed on the intermediate-layer armature to form an electro type magnetic pole. A skew symmetry exists between an upper-layer rotor and a corresponding lower-layer rotor, and the upper-layer rotor and the lower-layer rotor are rotated in opposite directions by commutation of the current flowing through exciting coils of the stator electrodes every T/N of time, wherein T is a rotation period of the upper-layer rotor, and N is the number of the magnets.

Abstract: An electromotive machine comprises a stator element and a rotor element, the stator element including at least one set of four toroidally shaped electromagnetic members, the electromagnetic members arranged along an arc a predetermined distance apart defining a stator arc length. Each of the members has a slot, and the rotor element comprises a disc adapted to pass through the slots. The disc contains a plurality of permanent magnet members spaced side by side about a periphery thereof and arranged so as to have alternating north-south polarities. These permanent magnet members are sized and spaced such that within the stator arc length the ratio of stator members to permanent magnet, members is about four to six. The electromagnetic members are energized in a four phase push-pull fashion to create high torque and smooth operation.

Abstract: A revolving speed increasing apparatus in which the repulsion of the magnets acts effectively only in the rotational direction to increase the revolving speed by the magnets. A rotary plate, fixed to a rotary shaft so as to integrally rotate, and a fixed plate, fixed to a stationary portion, are opposed to each other. A plurality of radially arranged elongated magnets provided at equal intervals, magnets for demagnetization fixed to the elongated magnets on one side thereof so as to protrude from the tips of the elongated magnets, and plate magnets arranged between the adjacent elongated magnets are provided on the opposed surfaces of the rotary plate and fixed plate. The rotary plate and the fixed plate are arranged with a rotational gap between the tip surfaces of the magnets for demagnetization. The poles at the opposed tips of the elongated magnets on the rotary plate and those on the fixed plate are of the same polarity.

Abstract: A stepping motor comprises a stator (3) with at least two magnetic circuits and a rotor (2) that is rotatably mounted on the stator through a single ball bearing having four contact points. The rotor comprises a multipolar magnet (5) essentially in the form of a disc having a central opening (6). One rotor portion (7) is fixed at one radially external portion of the magnet (5), while one radially internal portion of the magnet is arranged within the air gap of said magnetic circuits.

Abstract: A a rotating electromagnetic actuator with limited stroke, including at least 2N poles on the stator, N being a whole number, energized by at least one energizer coil and N magnetized parts on the rotor arranged in an air gap of thickness E wherein each magnetized part is juxtaposed with at least one ferromagnetic part with a thickness e between 0 and E, defining one or two air gaps with a total length of E-e.